In a bowl, mix together the butter, parsley, grated garlic, salt, pepper, and crushed red pepper until everything is well combined.
Spread this delicious compound butter on the slices of bread.
Sprinkle a generous amount of shredded mozzarella cheese on top.
If you're using the air fryer, set it to 350 degrees Fahrenheit and cook for 6 minutes. Keep an eye on it until the cheese turns golden brown and melty.